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Compiler-specific Features
4.7.105 __uxtab16 intrinsic
This intrinsic inserts a UXTAB16 instruction into the instruction stream generated by the
compiler. It enables you to extract two 8-bit values from one operand, zero-extend them
to 16 bits each, and add the results to two 16-bit values from another operand.
unsigned int __uxtab16(unsigned int val1, unsigned int val2)
Where val2[7:0] and val2[23:16] hold the two 8-bit values to be zero-extended.
The __uxtab16 intrinsic returns the 8-bit values in val2, zero-extended to 16-bit values
and added to val1.
Example:
unsigned int extend_add(unsigned int val1, unsigned int val2)
{
unsigned int res;
}
res = __uxtab16(val1,val2); /* res[15:0] = ZeroExt(val2[7:0] to 16 bits)
+ val1[15:0]
res[31:16] = ZeroExt(val2[31:16] to 16 bits)
+ val1[31:16]
*/
return res;
See also
• ARMv6 SIMD intrinsics on page 4-109
• Instruction summary on page 4-2 in the Assembler Guide
• SXT, SXTA, UXT, and UXTA on page 4-109 in the Assembler Guide.
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